Fluid pressure operated chuck



De. 28, 1943. E. A. F. REE iMER 2,338,060

FLUID PRESSURE OPERATED CHUCK Filed May 1, 1943 /l0 invemfor Patented Dec. 28, 1943 FLUID PRESSURE OPERATE!) CHUCK Edwin A. F.-Red1ncr, Chicago, 111.

' Application May 1,'.1'94s, Serial No. 485,559

' :2 Claims.

This invention. relates to improvements in chucks and more particularly to a novel and improved means for operating the same by. fiuid pressure.

An object of the invention is to provide a novel and improved imechanism for pneumatically operating a chuck,:said mechanism utilizing a lever fulcrumed intermediate. its ends whereby the pressure effect may be greatly increased by utilizing such lever.

Another object of the invention is to provide in a device of the characterdescribed novel and improved means for pneumatically operating a chuck, said means being effective for operation with a standard and conventional collet.

A'still further object of the invention is to provide ina device of the character described ndvel and improved meansutilizing fluid pressure operating'on a fulcrumed lever for trans-' mitting the force of said fluid pressure at an increased rate to the gripping means of said chuck, said device being capable of operation with a standard or conventional collet.

A still' further object of the invention is to provide a device of the character described which will be simple in construction, assembly and operation, which may be produced alon lines convenient for low cost manufacture, and which will at the same tim be highly eificient for carrying out the purposes for which it is designed.

With the foregoing and other objects in View which will appear as the description proceeds, the invention consists in certain novel features of construction, arrangement and combination of parts, hereinafter'fully described, illustrated in the'accomp'anying drawing, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportion, size and minor details of the structure may be made without departing from the spiritor sacrificing any of the advantages of the invention".

For the purpose of facilitating an understanding of my invention, 1 have illustrated in the accompanying drawing a preferred embodiment thereof, from an inspection of which, when consldered in connection with the following description, my invention, its mode of construction, assembly and operation, and many of its advantages should be readily understood and appreelated.

Referring to the drawing in which the samecharacters of reference are employed to indicate corresponding or similar parts throughout the several figures of the drawing:

Fig. 1 is a top plan view of a chucking device embodying my invention with parts thereof being shown in dotted lines.

Fig. 2 is a longitudinal sectional view throughout the same taken substantially on the line 22 of Fig.1.

Fig. 3 is a transverse sectional view taken substantially'on line 3-3 of Fig. 2.

Stated generally, the invention contemplates the use in a device of the character described of a standard or conventional collet having associated with it a sleeve, a portion of the inner surface of which is tapered and arranged to engage an inclined outer surface of the collet for actuatingthe jaws thereof to a closed position,'said sleeve and'collet being disposed in a chuck housing with the collet fixedly mounted therein and the sleeve being capable of sliding movement relative to said housing' and collet. The chuck housing is formed integrally with a base on the under surface of which is fulcrumed a lever', one end of which is adapted to engage the lower edge of the sleeve for actuating the same and the other end of which lever is adapted for engagement by a fluid pressure operated piston whereby upon the admission of fluid pressure to the cylinder within which the-piston operates, the lever will be actuated to engage the sleeve to move the same in a direction for bringing about a closing of the collet jaws and the release of pressure will be effectivefor permitting the inherent tendency of the collet jaws to move the sleeve in the opposite direction and to thereby release said collet jaws.

Referring to the details of my invention, the

reference character 10 designates generally a base the under sideof which is hollowed out, as shown at H, and on the upper surface of which is formed adjacent one end thereof a chuck casing or housing l2. The chuck casing I2 is of hollow cylindrical formation and is adapted to receive therein the cylindrical sleeve 13 for slidable movement therein, said sleeve being provided adjacent its upper end with an inwardly inclined surface 14 on its inner face. The sleeve I3 is adapted to receive therein the collet [5 which may be of standard and conventional construction, having the spring tensioned jaws 16. The said jaws l6 are provided with outwardly inclined surfaces on their outer sides, as shown at I1, for engagement and cooperation with the inclined surfaces H of the sleeve.

Adjacent the upper end of the collet I5 there is provided an annular ledge I8 adapted to be engaged by the nose-piece l9, said nose-piece being provided with a depending annular portion, ihe lower end of which is internally threaded, as shown at 20, for threaded engagement with a threaded portion 2| provided adjacent the upper end of the chuck casing l2. It will be obvious that when the parts so far described are in assembled relation, the movement of the sleeve l3 in an upward direction will overcome the spring tension of the jaws I6 of the collet to cause them to tighten or close about the piece of work disposed therein; whereas movement of the said sleeve in the opposite direction will allow said jaws to open up thereby releasing any work that may be held therein.

Obviously the actuation of the sleeve I3 to close the jaws may be accomplished in a plurality of ways, either manually or pneumatically. In the embodiment illustrated, however, I show my preferred mechanism for actuating the said sleeve, said mechanism including a novel and improved pneumatic means.

Provided on the base Ill at the and remote from the chuck casing is an air cylinder 22, the same being suitably secured to the base by means of the screws 23 extending through suitable ears 24 provided on said cylinder or in some other suitable and well known manner. Disposed within the air cylinder 22 is a piston 25 to which is secured a stem or a shaft 26, said stem extending downwardly from the piston and through an opening provided therefor in the body [0. Surrounding the stem is a coil spring 21. said spring acting between the under side of the piston 25 and the upper surface of the body l0, and is arranged to urge the piston 25 in an upward direction, as viewed in Fig. 2.

Provided in the air cylinder 22 adjacent its upper end is a nipple 28 which connects the inside of the cylinder 22 with a suitable source of fluid pressure. Any suitable form of valve, not shown, for admitting pressure to and exhausting it from the said cylinder, can be provided.

Arranged within the hollowed out portion ll of the body if! is a lever 29, the said lever being pivoted or fulcrumed intermediate its ends on a rod 30 fixedly secured within the body to, said lever extending longitudinally of said body. The left-hand end of the lever is arranged so as to be engaged by the stem 28 of the piston 25, said stem pressing on the lever when the fluid pressure supply is on to cause the said lever to swing about its fulcrum in a counter-clockwise direction. In order to insure proper contacting engagement between the lower end of the stem and the lever, there is provided in said lower end of the stem a ball-bearing 3|, said ball-bearing engaging the lever to actuate the same, as shown in the drawing.

The other end of the lever 29 is bifurcated, as shown in the drawing, to provide a pair of arms 32 and 33, said arms being arranged so as to engage substantially diametrically opposed portions of the lower edge of the sleeve l3. In order to insure proper contacting engagement at all times between the arms of the lever and the edge of the sleeve, I have mounted in each of the arms suitable ball-bearings 34, said ball-bearings engaging the bottom edge of said sleeve, as shown more clearly in Fig. 3 of the drawing.

It will be obvious that upon the admission 25 will be caused to move downwardly against the action of the spring 21, which movement will be transmitted to the lever 29 by the engagement of the left-hand end of the said lever by the lower end of the stem 25.

This movement of the lever will cause it to be swung about its fulcrum 30, with the result that the bifurcated end thereof will engage the bottom edge of the sleeve l3 and move the same upwardly. This latter movement of the sleeve willcause the inclined surface 14 thereof to engage the inclined surfaces I! of the jaws of the collet and move the same into closed position, in which position said jaws will remain until the fluid pressure is released. Upon the release of the fluid pressure, the spring 21 will cause the piston -25 to rise, thereby releasing the pressure on the lever 29. The sleeve 13 will now be permitted to move downwardly which movement will be due to its own weight plus the spring tension of the Jaws H of the collet. The result of this downward movement will be to open the jaws and thereby release the work being held therein.

It will be obvious, by utilizing the fulcrumed lever 29, the pressure of the sleeve is considerably increased over what it would be if the fluid pressure were permitted to operate directly on the sleeve. This feature renders the device more effective and greatly multiplies the force of the fluid pressure.

It will also be obvious that the operator will have his hands free at all times, as a mere actuaof fluid pressure to the air cylinders 22, the piston tion of a valve will be all that is necessary for operating the entire chucking mechanism.

The chuck may be provided with a suitable stop, which in the embodiment illustrated comprises the rod 35, the lower portion oi! which is threaded, as shown at 36, said threaded portio'n being received in a sleeve 31 fixedly secured within the body I. The rod 35 may be adjusted to any height desired, and then held in such adjusted position by means of a set screw 38 mounted in the sleeve 31, as shown more clearly in the Fig. 2 of the drawing.

It will also be observed that the device is capable of use with a standard or conventional collet, which collet may be changed from time to time as desired to accommodate the special work to be worked upon. By merely removing the nose-piece, the collet and its cooperating, sleeve maybe readily removed and a collet and sleeve of different size may be inserted inits place.

It is believed that my invention, its mode of construction and assembly, and many of its advantages should be readily understood from the foregoing without further description, and it should also be manifest that while a preferred embodiment of the invention has been shown and described for illustrative purposes, the structural details are nevertheless capable of wide variation within the purview of my invention as defined in the appended claims.

What I claim and desire to secure by Letters Patent of the United States is:

1. In a chuck, a hollow body, a housing formed at one end of said body, an air chamber formed at the other end of said body, a sleeve slidably disposed in said housing, a collet disposed in said sleeve, means securing said collet against movement in said housing, cooperating means between said sleeve and collet for closing the jaws of said collet when the sleeve is moved in one direction and for permitting the opening of said jaws when said sleeve moves in the opposite direction, and means for moving said sleeve in said one direction only including a lever pivotally mounted in said hollow body and fluid pressure means acting on one end of said lever for moving the same.

2. In a chuck having a housing, a sleeve slidable in said housing, a collet.disposed in said sleeve, means for securing the collet against sliding movement in said housing, said collet including normally spread spring tensioned jaws, cooperating means including an inclined inner surface in said sleeve and an inclined outer surface in the collet for closing the jaws of said collet when the sleeve is moved in one direction, said spring tensioned jaws normally urging the sleeve .in the other direction to provide for opening of the jaws, means to close said jaws comprising a lever pivotally mounted intermediate its ends and having one end disposed to abut an end of said sleeve, means including a fluid pressure operated piston efiective on the other end of the lever to rock said lever in one direction only to move its first mentioned end into abutment with the sleeve to slide it over the collet and close the jaws, and means to return the piston to its initial position-when fluid pressure is relieved.

EDWIN A. F. REDMER. 

